Honda Acura NSX 1991 Service Manual page 716

Master Cylinder
Construction
1 .
A tandem master cylinder is adopted for the master cylinder in order to improve safety of the braking system. In add-
ition, a center valve method is introduced so as to match the anti-lock brake system operation.
The master cylinder has one reservoir tank which is connected to the cylinder sections by two small holes. It has two
pistons-primary and secondary, which are criss-cross connected with the calipers so that the fluid pressure works
separately on each system (front right wheel & rear left wheel, and front left wheel & rear right wheel).
A stop bolt for controlling movement of the primary piston is provided at the side of the master cylinder body.
A reed switch for detecting the brake fluid volume is also provided on the cap of the reservoir tank.
2. Operation
When the brake pedal is depressed, the secondary piston is pushed through the brake booster and the center valve B
is closed so that the fluid pressure is generated on the secondary side. At the same time, the primary piston is push-
ed by the secondary fluid pressure and the center valve A is closed so that braking fluid pressure is generated both
on the primary and secondary sides.
When the brake pedal is released, the primary and secondary pistons are returned to the original position by the
brake fluid pressure and piston spring.
PORT
PORT
VALVE A